Top 50 MySQL Interview Questions and Answers

Download or read book Top 50 MySQL Interview Questions and Answers written by Knowledge Powerhouse and published by . This book was released on 2016-12-23 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains basic to expert level MySQL interview questions that an interviewer asks. Each question is accompanied with an answer so that you can prepare for job interview in short time. We have compiled this list after attending dozens of technical interviews in top-notch companies like- Google, Facebook, Netflix, Amazon etc.Often, these questions and concepts are used in our daily programming work. But these are most helpful when an Interviewer is trying to test your deep knowledge of MySQL.The difficulty rating on these Questions varies from a Fresher level software programmer to a Senior software programmer. Once you go through them in the first pass, mark the questions that you could not answer by yourself. Then, in second pass go through only the difficult questions. After going through this book 2-3 times, you will be well prepared to face a technical interview on MySQL for an experienced programmer. Some of the questions are:How will you calculate the number of days between two dates in MySQL?What are the different types of Triggers in MySQL?What are the differences between Heap table and temporary table in MySQL?What is a Heap table in MySQL?What is the difference between BLOB and TEXT data type in MySQL?What will happen when AUTO_INVREMENT on an INTEGER column reaches MAX_VALUE in MySQL?What are the advantages of MySQL as compared with Oracle DB?What are the disadvantages of MySQL?What is the difference between CHAR and VARCHAR datatype in MySQL?What is the use of 'i_am_a_dummy flag' in MySQL?How can we get current date and time in MySQL?What is the difference between timestamp in Unix and MySQL?How will you limit a MySQL query to display only top 10 rows?What is automatic initialization and updating for TIMESTAMP in a MySQL table?How can we get the list of all the indexes on a table?What is SAVEPOINT in MySQL?17. What is the difference between ROLLBACK TO SAVEPOINT and RELEASE SAVEPOINT?How will you search for a String in MySQL column?How can we find the version of the MySQL server and the name of the current database by SELECT query?What is the use of IFNULL() operator in MySQL?How will you check if a table exists in MySQL?How will you see the structure of a table in MySQL?What are the objects that can be created by CREATE statement in MySQL?24. How will you see the current user logged into MySQL connection?How can you copy the structure of a table into another table without copying the data?What is the difference between Batch and Interactive modes of MySQL?How can we get a random number between 1 and 100 in MySQL?What is the difference between Primary key and Candidate key?What is a Federated table in MySQL?How will you get the comma separated values for a column in a MySQL Group query?How can we get the results from a table in a random order in MySQL?How can we prevent duplicate records in a MySQL table?How will you eliminate duplicate values from a query result in MySQL?How will you get the size of data in a MySQL table?What is the option in Amazon Web Services for MySQL?How can we manage multiple MySQL servers?How will you migrate your SQL Server database to MySQL?What is the difference between MySQL and Oracle?What is the order of privileges in MySQL?Is it ok to mention a table name in lower case while creation and in uppercase while retrieving data from MySQL DB?Why this query does not work in MySQL?What is mysqldump?What is the limitation of mysqldump?Can we run Javascript or Python code in MySQL?What are user-defined variables in MySQL?How will you optimize a SELECT query in MySQL?What are the different optimization techniques in MySQL?How can we optimize INSERT query in MySQL?How will you make MySQL system secure against attackers?How can you protect your MySQL server against Denial of Service attacks?